In post offices and businesses handling large quantities of mail, it is customary to transport the mail in large plastic trays. These trays are hand-loaded. This hand-loading is awkward and consumes a substantial amount of time. Furthermore, it is not unusual to spill mail in the process of loading. Accordingly, it is a primary object of the present invention to provide a system to automatically load articles into a container and, more specifically, to load mail into a tray. Other objects are to provide such a system which is easy to operate, which can operate continuously, and which is adjustable as to container size. Other objects, features and advantages will be apparent from the following description and appended claims.